The page Visibility options are as follows:
Public - Pages with this visibility setting can be viewed by all visitors to the site,
and these pages will be shown in the menu.
Private - Pages with this visibility setting can only be viewed by logged in users
belonging to groups who have permission to view the pages. Private pages' titles
do not show up in the site menu unless a user is logged in.
Registered - Same as Private, but the page titles will show up in the site menu.
Registered users can then view the pages by logging in. Visitors who pull up a
Registered page without logging in will be shown a login form.
Hidden - Hidden pages are essentially stand-alone pages that are not added to
the site menu, so unless you give the link to someone, they will not know about it.
None - Pages with Visibility set to None cannot be viewed at all. This is useful if
you want to create a page without it going live right away.